Internal combustion engine



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muy 3, 1923.

W. H. @mm-:w

INTERNAL COMBUSTION ENGINE Filed Aug. 4, 1920 2 Shee's-Sheet l W www M mw Wd mm C. R Y P. N Wd July 3,1923.

W. im, @mmm INTERNAL COMBUSTION ENGINE Filed Aug. 4, 1920 2 Sheets-Shea?l 2 www A van Patented July 3, 1923.

V UNITED STATES PATENT OFFICE.

*WALTER R. CRIDE'RpOF INlBIA'NAIOLIS, INDIAN', ASSIGNOR DF ONE-HALF TO HENRY R. CARROLL, OF E'VANSVILLE, INDIANA..

)INTERNI-ill ClvBSTION ENGINE.

AppIcation `filed August 1, 19550. Serial No. 401,230.

To allie/om t muy concern:

Be it known that I, WALTER lt. (Inician, a citizen of the United States, residing at lndianapolis, in the county of'lvlarion and State of Indiana, have invented certain neiv "and useful Improvements in Internal-Com bustion Engines, of which the following is a specification;

This invention relates to internal combustion engines. The object of the invention is to provide a simple form of explosive engine which is practically noiseless, which Will securehigh efficiency in opera tion, and which can be operated successfully with kerosene, crude oil, or other low grade liquid hydrocarbon fuel. Another object of the invention is to provide an explosive en'- gine of the type described, vvhich is provided With simple means for controlling the supply of liquid fuel tothe explosion or combustion chamber, said means doing avi/ay with the ordinary forms of carburetor or like device for vaporizing` the liquid fuel. Another object of the invention is to provide an explosive engine which is so arranged that prior to each explosion or ignition, a comparatively large volume of eX- plosive mixtureis positively forced under pressure into the explosion chamber', so as to secure high .efficiency in proportion to the dimensions of the` engine cylinder. @th-` er objects of the invention are in part obvious and in part will appear more in detail hereinafter. y

In the accompanying` drawings which illustrate one embodiment of the invention, F 1 is a view, partly` in sectionalelevation and partlyin side elevation,of part of a battery of engine cylinders, and showing a rotary valve; Fig. 2 is a sectional elevation on the` line 2&2, Fig. l.; Fig. 3 is a partial plan view `showing the rotary pump andthrottle valve; Fig.` 4 la detail sectional elevation, illustrating the fuel supply mechanism.; F ig. `5 is a detail sectional elevation of thethrottle valve; Fig. 6 is aV detail sectional elevation of a fuelfsupply controlling valve.; and Fig. `is a cross sec tional vieiv of the rotarypump and automatic controlling valve. l p y. f l i In the dra-Wings y1,represents an engine cylinder, Which is Water-jacketed as is usual, and is provided ,with bores of-different diameters, that is, a small bore 2vvhich forms the ignition or explosion chamber of the engine, and a large bore 3, which forms the chamber of anair pump, for forcing air under pressure, during the back stroke of the engine piston, into the ignition chamber. d represents the engine piston, which provided with a small head 5, Working in thesmall bore 2 of the cylinder, and a large head 6, ivorkingin thelarge bore 3 thereof. This piston is connected by the usual connecting rod 7' to a crank 8 on the main crank shaft 9 of the engine. The crank shaft may be surrounded or covered by a casing 10 secured to the engine cylinder, as is usual, although this is not essential in the present form of engine.

it one side of the small bore 2 theengine cylinder is formed to provide a substantially cylindrical valve chamber 11 With `its `axis transverse to the direction of movement of the piston. ilVithin said chamber is located a rotary valve, which controls both the eX haust of the exploded or burned gases from the ignition chamber of the. engine cylinder, and also the admission of the main portion of the air thereinto. As illustrated, the

rotary valve` comprises a plug or member 12, ,having a. single long diametrical or cross port or passage 13 therethrough. The plug 1Q is contained Within a conical sleeve 14, which may be adjusted longitudinally in the casing by end bushings 15 threaded there# into, so as to take up Wear or to tighten `the valve. Said bushings are provided with inner raceivays to receive balls or rollers 16 which are contacted by cones 17 secured to the valve shaft. A separate rotary valve is provided for each of the several engine cylinders, and these valves are arranged end to end or in line with each other. Preferaw bly, the several valve shafts `Will be con `nected to each other, as at 17u, by suitable universal couplings, so that they ivill rotate as one, and which couplings `will take care of any chance misalignment of the 4valve shafts. One of the valve shafts, such as the end shaft, is provided with a suitable gear ,p

or sprocket wheel 171 driven by anysuitable mechanical connection to the y crank shaft, the `gearing being so proportioned that the valve shaft rotates at one-half the speed of the crank shaft.

f The transverse port 13 through the valve plug 12 is adapted in one position of the valve to open communication from a port 18, leading directly through the wall of the engine cylinder from the lower part of the ignition chamber 2 thereof, to an exhaust port 19, leading to the open atmosphere. In another position of the valve the through passage therein opens communication from `a passage 20 in the cylinder wall, communi eating with the air chamber 3 to a passage 2l in the cylinder wall, communicating with the ignition chamber'2.

One end of the engine cylinder, such as the upper end, is provided with a suitable air inlet valve, for admitting air into the ignition chamber 2 of the engine cylinder to scavenge or free the same of spent gases. Inthe form. shown', a sleeve 22 is threaded into the end head of the cylinder, said sleeve being provided with across wall carrying an inner tubular member or sleeve 23, which forms a: guide for the spindle 25 lof the valve. VThe valve seats at 2,6 against the inner end of sleeve 22. The outer end of thev sleeve 22 forms a eusliioningchamber 27,l which contains a spring 28 seated at one end against the transverse wall of the sleeve 22 and yat its other end against a cap or head 29, which slides within sleeve 22 and closes the outer end of chamber 27. lSpring 28 holds the valve to its seat, and chamber 27 forms'a,v cushion to assistin cushioning the valve, whilel the end cap or head 29 prevents noise or popping of the valve, The

' end head of the engine cylinder is provided with a plurality of air ports or openings 30,

. surrounding the valve 25, which'le'ad to a space `3l within the wall of the end head. The lowerportion of the wall of sleeve 22 is also provided with a plurality of radially extending ports or openings 32, opening communication' from the space 31 to the space Withinthe sleeve` 22 below its cross wall"v and above the valve.

Figs. 3,'4 and6 illustrate in detail the arrangement for supplying fuel to the several engine cylinders, which is claimed and de` scribed more in detail 'in my co-pending application filed of even date herewith, Serial No. 401,360. As illustrated herein, 33 indicates a shaft, provided with a. gear or sprocket 33, by which it is driven in timed relation with the main crank shaft 9 of the 55 engine by any suitable connection, such as by a chain or the like. Said shaft 33, in the particular type and arrangement of engine illustrated, rotates at the same speed as the main crankshaft. Shaft 33 carries one of theinter-geared members 34 of a 'rotary pump provided with a supplyconnection 35 v to atank or reservoir (not shown) for holding a supply of kerosenecrude oil, gasoline, or any other suitable or preferred liquid hy` drocarbon fuel. The pump 34 rotates continuously with the main crank shaft and de` livers or discharges, under pressure, a supply of the liquid hydrocarbon fuel into a space or passage 36. 35 represents a check valve arranged to prevent the fuel from returning to the supply reservoir when the engine is not ruiming. Shaft extends alongthe side of all of the several engine cylinders, and passes through casings 37 bolted or otherwise connected to the sides thereof. Suitable stufling boxes 3S are provided for the shaft 33 at the several casings 37. The main portion of shaft is hollow or tubular, so as to form an inner space or chamber 39, which at one end is in com` munication, through a plurality of circumferentially -spaced ports or openings 40, with` the passage 36, whereby the liquid hydr0- carbon fuel is fed into the tubular shaft. Each of the casings 37 is provided with an inner sleeve or tubular portion 41 having a small port 42 therethrough, said port terminating at its up )er end in a valve seat 43. The tubular shaft 33 is provided with ports or openings 44, one for each of the several engine cylinders, said ports being arranged, relatively to each other, so as to move into and out of registration with the` several ports 42, to thereby supply successive charges of liquid hydrocarbon fuel to the fuel supply chambers within the casings 37 of the several engine cylinders, in thel proper order.

The upper portion of each casing 37 is provided with a threaded bore to receive a hollow threaded plug 45. Within said plug is a valve 46, held to its seat 43 by a Vspring 47. The tension of this spring can be regulated by adjusting the plug 45 in its threaded socket, and the plug can be secured in adjusted position by a lock nut 48.

The fuel supply chamber within each casing 37 is in communication, through two ports or passages, marked 51 and 52, respectively, with a pump chamber or bore 50 in one side wall of the smaller portion of the engine cylinder. A transverse wall or bridge 53, divides the space within the casing 37, so that any air admitted through port 51, as hereinafter described, can only pass to the port 52 by flowing entirely around and over the inner sleeve 41 within said casing. l

Hthin the cylinder or bore 50 is a piston or plunger 54, the upper end of which is of full size and a sliding fit within said bore, while the lower en-d is reduced, as at `Said piston is firmly attached to the engine piston 4, as by being threaded thereinto, and may be provided with one or more annular grooves 56, to hold oil, to lubricate and seal or pack the plunger in its bore. The lower end of the bore 50 is in communication with the air chamber 3v above the large head 6 of the piston.

The reciprocating piston or plunger 54 forms a pump for forcing a measured supply of mixed air and hydrocarbon fuel under pressure into the combustion chamber 2 of the engine cylinder. The time of this supply is regulated by a valve, shown in detail in Fig. 6. As illustrated, a sleeve or hollow plug 6() is threaded into the upper end of the bore 50, said sleeve being provided `with an inner seat 61 at its lower end, against which seats a ball valve 62. Said ball valve is held downwardly by a plunger v63 guided in its movement on a spindle 64 projecting downwardly from the lower end of an adjusting plug 65, which plug is threaded into the hollow sleeve 60. A tension spring 66 is located between the plug and the upper end of plunger 63, so that the tension on the ball valve 62 may be adjusted. A lock nut 67 holds the plug in adjusted position. Communication is open through the valve and through a port 68 in the side wall of the engine cylinder, from the bore 50 of the fuel pump 'to the engine cylinder.

Assume that in the position of the parts shown in Fig. `2, a charge of mixed hydrocarbon fuel and air has just been explodedor ignited in the chamber formed by the small bore 2 of the engine cylinder. The explosion `may be caused by an electric spark, or by other suitable ignition device, now shown, or the mixture may be caused to ignite and `burn gradually merely bythe rise of its temperature as a result of highly compressing the charge. The expansion of the exploded or burned gases forces the piston downwardly. The rotary valve occupies the position shown in F ig. 2 and has just cut off communication between the passages 2O and 21. It is rotating in the direction shown by the arrow A. yThe piston moves downwardly until the side port or passage 18 is uncovered by the upper end thereof, at lwhich time the rotary valve opens communication between the ports 18 and 19. There is therefore a sudden exhaust of the exploded, burned or spent gases through the exhaust port 19. The rush of the exploded gases outwardly and the sudden suction caused by the quick downward movement of the piston, produces a siphoning action which sucks in a quantity of air through the air admission valve in the head of the cylinder. `This airreplaces some, if not all, of the spent gases in the engine cylinder and therefore scavenges the same.

`charge of compressed air, with the liquid hydrocarbcn fuel absorbed thereby, or mixed therewith, consequently flows into the space above the piston or plunger 511.

As the engine piston begins to move upwardly on the back stroke, the rotary valve i graduallyopens communication between the passages 20 and 21. The air trapped above the large head of the piston, and within the chamber 3, is therefore forced upwardly through the passage 20, the passage 13 in the rotary valve, and passage 21,into the space 2 above the small head of the piston, thereby supplying a second charge of clean air under pressure to the small bore or ignition chamA `ber of the engine cylinder. This supply of air continues until the piston covers the open end of the passage 21, thereby shutting ofi' further supply of air, leaving, however, a smaller quantity of air trapped above the large head of the piston, since the latter has not quite reached. lthe upper limit of its movement.

During the early part of the upward move ment of the piston, the upper end of the pump piston or plunger 541 covered the port 52 leading from the fuel supply casing 37 into the bore 50. Further upward movement of the piston or plunger 5a compresses the `charge of mixed gas and air which has entered the pump cylinder.` J ust after the piston 5 closes the open end of the passage 21 and shuts off further supply of air to the `engine cylinder, the pressure accumulated in cylinder 50 above the plunger 54|: becomes greater than that within the engine cylinder. This raises the valve 62 from its seat and produces a sudden inrush of the charge of mixed fuel and air under pressure above the plunger 54 into the engine cylinder, which produces a thorough vaporization of all of the liquid hydrocarbon and completes the mixture thereof with the air, so that a good or complete combustion inthe engine cylider is effected.`

When the piston, during its upward movement covers the passage 21, the plunger 5ft uncovers the port 51, thereby opening `cemmunication from the air space 3 above the large head 6 of the piston, through the bore `50 of the pump cylinder around the reduced lower end 55 of the j olunger, into the fuel supply chamber within the casing 37. The large head of the engine piston therefore forces a quantity of air into the casing 37.

It will be understood, however, that shortly before this occurs, that is, about midway of vthe period of upward movement of the piston, the fuel supplyshaft 33 reaches a ythe hollow tube into the space within casing 37. Vhen lthe air rushes into this casing beneath the bridge 53 and up over the sleeve 41, it laps up or absorbs the liquid hydrocarbon, and begins to vaporize thesame at the high ypressure under which the air is introduced into the casing.,y Vhen the piston again begins to move downwardly the lower end of the plunger 54 covers ports 52 and 51 and traps the compressed air in casing 37, so that it is ready to rush into the space above the plunger 54 when it reaches its` lowest position of movement and uncovers port52.. f

yIt will be understood that the rotary-pump 34 operates continuously, so that a supply of liquid fuel is constantly being introduce-d into the space within the hollow shaft 33. For this reason a suitable relief valve may be attached to shaft 33, so as to take care of the variation in volume of the space within said shaft when all of the supply ports 44 for the severalcylinders of the enginel are closed at the same time, and to also furnish the engine.

7 and islocated in a connection 100 leadingy from the supply spaceor passage 36 back maximum.

means-for limiting. thel maximum speed of Such a valve is shown in Fig.

to the main supply reservoir. The valve comprises a casing'provided with a cross wall having a valve seat 101 against which seats lvalve 102. This valve is held to its seat by a spring 103,th`e tension of which may be regulated or adjusted by a sleeve 104 threaded into the casing. By adjusting the tension of the `spring to the proper amount, the valve may be so set that any fuel supplied by the pump which is in eX- cess of a given amount will be returned to the supply tank. vThe speed ofthe engine depends upon the amount of Ifuel supplied thereto and thereforecan be set at any The valve also acts as a relief valve for when the pressure of the oil in the supply passage 36 becomes too great the valve 102 is lifted and part of the oil flows back as before.

90,".Fig. 3, represents a throttle valve, shown in detail fin Fig. 5. As illustrated,

4this valve comprises a casing 91 threaded into casing 37 and opensat its lower end to the fuel vsupply passage 36.y The casing' 91 is `provided with a cross wall 92 having a plurality of circumferentially arranged ports 93 therethrough. The space 94 on the upper-side of said wall is provided with a connection 95 leading back to the supply tank or reservoir for containing the liquid vhydrocarbon fuel.` Journaled in a boss 1n the end wall vof the valve casing, and projecting through the transverse wall 92, is a shaft 96, having a controlling valve or plate 97 on its inner end. Said plate is provided with a plurality of ports or openings 98 adapted to be moved more or less into registration with the ports 93, so that communication through the wall 92, between the chambers 'on opposite sides of said wall, can be regulated. Shaft 96 can be operated by a suitable hand lever or the like. lYhen it is desired to throttle the engine, to control its speed, shaft 96 is adjusted to open the ports 94 more or less and thereby return a portion of the liquid hydrocarbon fuel delivered by the pump 34 to the supply tank or reservoir. A suitable indicator may be attached to the shaft 96, so that it can be placed in the proper position to throttle the engine down to any particular number of revolutions per minute. Valve 90 may be used either with or without the automatic feed control valve 102 heretofore referred to.

The engine described is of the two-cycle type and is very simple, both in operation and in construction. It performs all, the usual functions of gas engines, but in addition is provided with a rotary valve for simultaneously controlling the exhaust of the spent gases and the introduction of plain air `into the explosion cylinder. It therefore does away with the objectionable noise produced by the ordinary poppet valves used on gas engines. For the amount of power that it will develop it is exceedingly small and light and is therefore particularly well adapted for use on flying machines. However, it is also well adapted for use on automobiles or in stationary installations. The fuel supply system is simple and can be regulated so as to furnish the proper quantity of fuel to produce any number of revolutions per minute of the main crank shaft. Moreover, the liquid hydrocarbon fuel is introduced into each of the engine cylinders in measured charges, equal to the capacity of the space within the bore 50 above the pump plunger` 54.

The arrangement of valves specified, enables the charge to be highly compressed and then introduced suddenly into the engine cylinder', thereby securing complete vaporization of the liquid fuel without any necessity of heating the same. I `urthermore,y the charge is introduced subsequent to the preliminary scavenging of the engine cylinder through the valve at the end thereof, and also subsequent to the introduction into the cylinder of a second quantity of air under pressure from the chamber 3 so that the hytion.` For this reason the engine will op erate with kerosene, crude oil, or any other low grade fuels, although it will of course be understood that it can be operated equally as well with the better grades of fuel.

`What I'claim `is:-

1. In an'internal combustion engine, the combination of a cylinder having a combus tion chamber, a piston movable in said chamber, means for admitting fuel to said chamber, a single valve for controlling the exhaust of the spent gases from said chambei' and the supply of air thereto, operating connections for said valve whereby it opens the air supply to the combustion chamber during the compression stroke of the piston and a valve at the opposite side of the chamm ber to control` the supply of fuel thereto, substantially as set forth. i

2. In an internal combustion engine, the

`combinationof a cylinder having acombustion chamber, a piston movable in said chamber,umeans for `admitting fuel to said chamber, a rotary valve arranged in one position to openocommunicatio'n from said chamber toexhaust and in another position to `admit air to said chamber, operating connections for said valve so arranged that air is suppliedto said chamber on the compression stroke of the piston and a scavenging valve at the end of the cylinder, substantially as set forth. i

3. In an `internal combustion engine, the combination of a cylinder having a combustion chamber and an air chamber.' a scavenging valve in one end of said cylinder, said valve opening inwardly, a piston having two heads, one in each of said chambers, means for forcing fuel into said combustionchamber, and a'vsingle valve for controlling` communication between said chamber andthe exhaust from said combustion chamber, saidk scavenging` valve being arranged to open when said last named valve opensthe exhaust from the combustion chamber.

` 4. In an internal combustion engine, the combination of a cylinder having a oombustion chamber and an air chamber provided with aport leadingto the atmosphere, a piston movable in said cylinder and provided with two heads, one in each of said chambers, means for admitting a charge of mixed fuel and air into the combustion chamber, a passage connecting said. chambers, and a single valve in said passage arranged to control the exhaust from said chamber and to admit a supply of clean air from `the air chamber into the combustion chamber.

5. In an internal combustion engine, the combination of a cylinder 4having a combus tion chamber andan air chamber provided with a port open to the atmosphere, a piston movable in said cylinder and provided with two heads,` onein each of said chambers,

means operated by said piston for forcing fuel into said combustion chamber, and a valve arranged to simultaneously control the exhaust of spent gases from said combustion chamber and communication between said chambers.

6. In an internal combustion engine, the combination of a` cylinder having a combustion chamber and an air chamber provided with a port open to the atmosphere, a piston movable in said cylinder and provided with two heads, one in each of said chambers, means including a valve for admitting` fuel to the combustion chamber, ,and a rotary valve arranged in one position to open communication from the combustion chamber to exhaust and during the compression stroke of the piston to open communication between said air and combustion chambers, said fuel supply valve being arranged to open near the endof the compression stroke of the piston.

7. In an internal combustion engine, the combination of a cylinder having a combustion chamber, a piston movable in said cylinder, a valve arranged to simultaneously control the exhaust from said chamber and the admission of air thereto, means whereby the piston on its compression stroke forces air into the combustion chamber, a pump cylinder provided with connections `to a fuel supply, and a plunger connected to the engine piston and working in said pump cylinder and arranged to forcefuel into the combustion chamber. i

8L In an internal combustion engine, the combination of a` cylinder' having a. combustion chamber, a piston movable in said cylinder, a `valve arranged to simultaneously control the exhaust from said chamber and the admission of air thereto,` said valve bef ing arranged to open the air supply to said chamber during the compression stroke of the piston, a pump cylinder provided with connections to a fuel supply, a plunger conneoted to the engine piston and workingin said pump cylinder and arranged to force fuel into the combustion chamber, and a valve controlling communication between the pump cylinder and the combustion chamber.

9. In an internal combustion engine, the combination of a cylinder having a combustion chamber and an air chamber. a piston movable in said cylinder and provided with two heads, one in each of said chambers, means for-admitting air to the combustion chamber, a pump cylinder communicating with said combustion chamber, a casing forming a fuel supply` chamber communicating with said pump cylinder and with said air chamber, and a plunger working in said pump cylinder and arranged to control communication between the air chamber and the fuel supply chamber, and between the fuel supplychamber and the pump cylinder, said plunger being adapted to force fuel into the combustion chamber.`

10. In an internal combustion engine, the combination of a cylinder having a combustion chamber and an air chamber, a piston movable in said `cylinder and provided with two heads, one in each of said chambers, means for admitting air to the combustion chamber, a pump cylinder communicating at one end with said combustion chamber and at the other end'with said air chamber, a plunger connected to said piston and working in said pump cylinder, and a casing communicating with said pump cylinder and provided with connections to a fuel supply, said plunger being arranged to control communication between said air chamber and said fuel supply chamber and between said fuel supply chamber and the'space in said pump cylinder above said plunger.

11. In an internal combustion engine, the combination of a cylinder having a combustion chamber and anV air chamber, a piston movable in said cylinder and provided with two heads, one in each of said chambers, means for admitting airto the combustion chamber, a pump cylinder communicating at one end with said combustion chamber and at the other end with said air chamber, a plunger connected to said piston and working 4in said pump cylinder, a casing communicating with said pump cylinder and provided with connections to a fuel supply, said plunger being arranged to control communication bet-Ween said air chamber and said fuel supply chamber, and between said fuel supply chamber and the space in said pump cylinder above said plunger, and a valve in the passage between the pump cylinder and combustion chamber and arranged to control the supply of fuel to the combustion chamber.

12. In an internal combustion engine, the combination of a cylinder having a combustion chamber and an air chamber, a piston movable in vsaid cylinder and having two heads, one in each of said chambers, a pump cylinder communicating at its opposite ends with said chambers, a casing forming a fuel supply chamber and communicating with the pump cylinder, a conduit leading into said fuel supply chamber, a valve controlling communication between said conduit and the fuel supply chamber, and a plunger working in the pump cylinder and arranged to force fuel from the fuel supply chamber into the combustion chamber.

13. In an internal combustion engine, the combination-of a cylinder having a combustion chamber and an air chamber, a piston movable in said cylinder and provided with twoheads, one in each of said chambers, means for admitting air to said combustion chamber, a casing forming a" fuel supply chamber and provided with communications to said combustion chamber, and a hollow shaft forming a fuel supply conduit and rotatable in said casing, said casing and hollow shaft being provided with ports adapted to control communication between the hollow shaft and fuel supply chamber.

14. In an internal co1nbustion`engine, the combination of a cylinder having a combustion chamber and an air chamber, a piston movable in said cylinder and provided with two heads, one in each of said chambers, means for admitting air to said combustion chamber, a casing forming a fuel supply chamber and provided with communications to said combustion chamber, a hollow shaft forminga supply conduit and rotatable in said casing, said casing and hollow shaft being provided with ports adapted to control communication between the hollow shaft and fuel supply chamber, a yielding valve arranged to normally prevent the passage of fuel through said ports, and pressure means for forcing fuel through said hollow shaft.

15. In an internal combustion engine, a cylinder having a combustion chamber and an air chamber, a piston forming a movable partition between said chambers, a pair of' by-passes leading around said piston from said air chamber to said combustion chamber, a fuel passage communicating with one of said by-passes, and means to force air through said passages to supply the combustion chamber with mixed air and fuel and with pure air respectively. substantially as set forth.

16. In an internal combustion engine, aoylinder, a piston therein having an upper head which is acted upon by an explosive mixture and a larger lower head integral with 'the said upper head, a bore parallel ,to the cylinder and opening into the cylinder above the upper head of the piston, a, fuel passage `leading into said bore, a plunger secured in the top of the larger head of the piston having a head extending upwardly 'through the bore and adapted to force a mixture of air and fuel through the bore and into the cylinder, substantially as set forth.

17. In an internal combustion engine, a cylinder having a combustion chamber and an air chamber, a piston having a head in each chamber, means operated by the head in the air chamber to supply mixed air and fuel to said combustion chamber, and a separate passage in the cylinder to supply pure air in greater quantity thereto. said passage connecting the chambers at their upper ends whereby upward movement of the head in the air chamber forces air into the combustion chamber, substantially as set forth.

18. In an internal combustion engine, a cylinder, a piston therein having an upper head and an integral lower head of larger diameter, a bore parallel to the cylinder opening into the cylinder above the upper head of the piston, fuel passage leading into saidbore,` and means to force a mixture of air and fuel through the bore and into the cylinder comprising a pump piston in the bore fixed to the piston thereber to torce air from said chamber into said by-passes, substantially as set forth.

20. In an internal combustion engine, a cylinder, a piston therein having an upper head and a lower head of greater diameter and integral with the upper head.l a bore parallel to and extending the length ott the said upper head and opening into the cyl-- inder above the upper piston, a mixing chamber ior air and 'fuel communicating with said bore, means tor forcing air into said mixing chamber, a plunger in the bore secured to and extending1 iupwardly from the lower head of the piston and adapted to force mixed air and fuel into the cylinder, and a spring-pressed valve normally closing the opening leading to the cylinder, substantially as set i'orth.

2l. In an internal combustion engine, a cylinder, a piston therein, a scavenging passage at the end oit' the cylinder, and a spring seated valve provided with an air cushioning mechanism, said valve being operated by the piston on its suction stroke to admit air through said passage7 substantially as set iorth.

In `an internal combustion engine, a cylinder having a combustion chamber and an air chamber, a piston having a head in said combustion chamber, a valve at one side of the head, a by-pass between said chambers and an exhaust passage, both alternately opened and closed by said valve, fuel feeding means spaced from said bypass, and a piston head in said air charnber for compressingthe air therein and forcing it into the ley-pass, substantially as set iiorth.

said combustion chamber, a valve at one y side of the head, a by-pass between said chambers and an exhaust passage, both alternately opened and closed by said valve, fuel feeding means spaced from said bypass, a piston head in said air chamber for compressing the air therein and forcing it into the by-pass and an inlet opening tor air extending through the wall of the cylinder to said air chamber, substantially as set forth.

2st. In a two-cycle internal combustion engine, a cylinder, a piston, a fuel passage, an independent air passage leading to the cylinder, exhaust and scavenging passages, each of said passages opening independently into the cylinder, means to open the exhaust and scavenging passages during one 'stroke of the piston, means to open the air passage and force air into the combustion chamber during the other stroke and means acting near the end of the second strolre to inject mixed air and fuel into the combustion chamber, substantially as set forth.

2'5. In an internal combustion engine, a cylinder having a combustion chamber and a compression chamber, a piston having two heads, one in each chamber, a bore parallel to said chamber and communicating' therewith at its upper end, a mixing chamber for air and fuel communieating` with said bore, a plunger in said bore lixed to the piston head in the compression chamber and a passage from said compression chamber to said mixing chamber and adapted to be opened and closed by said plunger, substantially as set forth.

26. In an internal combustion engine, a cylinder having a compression chamber communicating at times with the atmosphere and a combustion chamber, a piston having a head in each chamber, a mixing chamber for air and liquid fuel, a passage for supplying air thereto from said compression chamber and another passage ttor supplying air under pressure to the combustion chamber, substantially as set forth.

In witness whereof, I have hereunto set my hand and seal at Indianapolis, Indiana, this 28th day of July, A.. D. nineteen hundred and twenty.

WALTER R. CRIDER. [Ls] Vllitnesses:

Jas. T. Moons', MARY A. GILL. 

